Solenoid controlled flow valve

Abstract

A pilot operated flow regulating valve which can be remotely controlled by varying the energization to a solenoid. The valve consists of a normally-closed, spring-biased, pressure-differential-actuated, main valve element and a pressure-compensated, pilot flow valve employing a solenoid acting like a remotely controllable electromagnetic spring to control the flow of fluid through the pilot valve and the pressure difference across the main valve element.

Having described our invention, we claim: 
     
       1. An electrically controlled pilot actuated flow valve comprised of: a. a housing having an elongated cylindrical cavity with a pressure inlet port and at least one radially facing main outlet port;   b. a main valve element operable to control the flow of fluid between said inlet and outlet ports;   c. said main element having a first axially facing surface exposed to inlet pressure and a second oppositely facing surface defining with said cavity a variable pressure chamber;   d. means biasing said main valve element to an initial position relative to said inlet and outlet ports;   e. a main valve orifice communicating said inlet port with said variable pressure chamber;   f. a pilot valve outlet port adapted to communicate said variable pressure chamber to low pressure;   g. a pilot valve element operable to control the flow of fluid from said chamber through said pilot valve outlet port;   h. pressure differential responsive means biasing said pilot valve element in one direction to restrict said flow from said chamber;   i. an armature supporting field pole and an axially spaced armature attracting field pole;   j. a solenoid coil surrounding said poles; and,   k. a magnetically permeable armature operatively associated with said pilot valve element and having a first end substantially overlapping said supporting field pole and a second end slightly overlapping said attracting field pole and operable when said coil is energized to exert a magnetic force on said pilot valve element in an opposite direction to move it to a new position relative to said pilot valve outlet port.   
     
     
       2. The valve of claim 1 wherein said means includes an axially facing orifice operatively associated with said pilot valve element through which all fluid flowing through said pilot valve outlet port flows to create a pressure force on said pilot valve element opposite to magnetic forces on said armature. 
     
     
       3. The valve of claim 1 wherein said pilot valve outlet port opens radially into said variable pressure chamber and said pilot valve element moves axially. 
     
     
       4. The valve of claim 2 wherein said pilot valve outlet port opens radially into said variable pressure chamber and said pilot valve element moves axially. 
     
     
       5. The valve of claim 1 wherein an edge of said main outlet port adjacent the inlet port extends circumferentially and said main valve element moves axially. 
     
     
       6. The valve of claim 2 wherein an edge of said main outlet port adjacent the inlet port extends circumferentially and said main valve element moves axially. 
     
     
       7. The valve of claim 1 wherein said main outlet port is rectangular with one wall extending circumferentially. 
     
     
       8. The valve of claim 2 wherein said main outlet port is rectangular with one wall extending circumferentially. 
     
     
       9. An electrically controlled flow valve comprising in combination: a spring-biased, normally-closed, pressure-differential-actuated main flow valve having a pressure inlet, a main outlet and a variable pressure outlet with the difference in pressures between pressure inlet and variable pressure outlet determining the communication between pressure inlet and main outlet; and a pressure compensated pilot flow valve in series with said variable pressure outlet and a low pressure outlet, and variable spring means for establishing the rate of flow of fluid through said pilot valve. 
     
     
       10. The valve of claim 3 wherein said spring means include an electro-magnetic spring biasing said pilot valve to the open position in an amount proportional to the electrical energization of said electro-magnetic spring. 
     
     
       11. The valve of claim 3 wherein mechanical spring means bias said pilot valve to the open position and a solenoid-armature arrangement creates a force opposing the force of said mechanical spring to move the pilot valve to a partially closed position in an amount proportional to the electrical energization of said solenoid. 
     
     
       12. In an electrically controlled flow valve comprising in combination: a spring-biased, pressure-differential actuated main valve; an adjustable pilot flow valve, the flow of which, when varied, varies the pressure difference on said main valve; the improvement which comprises said pilot flow valve being of the pressure compensated type; and electro-magnetic means for varying the flow of fluid through said pilot valve and the pressure differential across said main valve. 
     
     
       13. An electrically controlled pilot actuated flow valve comprised of: a. a housing having an elongated cylindrical cavity with a pressure inlet port and at least one radially facing main outlet port;   b. a main valve element operable to control the flow of fluid between said ports;   c. said main element having a first axially facing surface exposed to inlet pressure and a second oppositely facing surface defining with said cavity a first variable pressure chamber;   d. a pilot valve element having a first axially facing surface exposed to the pressure in said first variable pressure chamber and a second axially facing surface defining with said cavity a second variable pressure chamber;   e. main valve means biasing said main element to an initial closed position relative to said ports;   f. a main valve orifice communicating said inlet port with said first chamber;   g. a pilot valve outlet port adapted to communicate said second variable pressure chamber to low pressure;   h. said pilot valve element being operable to control the flow of fluid from said second chamber through said pilot valve outlet port;   i. means in the form of an orifice communicating said variable pressure chambers, resulting in pressure differentials biasing said pilot valve element in one direction to restrict said flow from said second chamber; and,   j. other means for adjustably and resiliently biasing said pilot valve element in the opposite direction to permit flow from said second chamber to said pilot valve outlet port.   
     
     
       14. The valve of claim 1 wherein said means of subparagraph i includes an orifice operatively associated with said pilot valve element through which all fluid flowing through said pilot valve outlet port flows, said element having axially oppositely facing surfaces exposed to the pressure differential across said orifice to create a pressure differential force on said pilot valve element opposite to said bias means of subparagraph i.